Modal auxiliary verbs
Modals auxiliary verbs are a very complex area of English grammar, so in this quick guide we will not be able to go into much detail, but we will at least get an overall idea of what their function is in a sentence. In an earlier section of this guide we looked at how the verb phrase can be broken down into its constituent parts and we noted that one of these parts was called a modal auxiliary verb.
Let’s look at each modal verb separately, and the functions they help to express:
Can: Can is used
1) to express ability:
- Can you speak Mandarin?
- She could play the piano when she was five.
2) to express request:
- Can you help Sue?
- Can I offer you something to drink?
3) to express permission:
- Can I use your cell phone?
- You can’t go out with Victor.
4) to express possible:
- If the weather is perfect tomorrow, we can go on a picnic.
- I can be ready by five.
- I will be ready five.
＊ Can is used to express a statement that is less uncertain than will.
5) be able to: be able to is used to describe an ability that a person will have in the future.
- My baby will be able to walk in a few months.
- I am busy but I will be able to talk to you in ten minutes.
Could: Could is used
1) to express abilities in the past:
- Jason could do 50 push-ups in five minutes when he was young.
- Jason could talk when he was four.
2) to express permission:
- Could you lend me two grants?
3) to express future possibility: it expresses more uncertainty than may
- I could get an A or B in grammar. It depends on the final exam.
4) could with present perfect tense is used to express something in the past may be real.
- You could have been killed in that accident.
- I could have won that game.
1) Making offers
- Shall I fetch you another glass of wine?
2) Making suggestions
- Shall we go to the cinema tonight?
Will: Will is used
1) present to future tense:
- Sean will leave tomorrow. She will be back in a few days.
- If it rains, the soccer game will be put off.
2) express willing,
- If you won’t go and help him, I will.
- I will wash the dishes if you cook.
Would: Would is used
1) as the past tense of will:
- She said she would buy dinner on her way home.
- I believed it would rain so I brought my raincoat.
2) to express polite request:
- Would you please take off your coat?
- Would you mind turning the radio off?
3) to express actions take place in the past:
- I would fish and swim in the river when I lived in the countryside.
- I used to go swimming in the river when I lived in the countryside.
4) to express desire
- I would like to have one day off.
- I’d love to stay for a few more days.
Should: Should is used
1) to give advice and opinions
- You are driving too fast; you should slow down a little bit.
- You have gained a lot of weight. You should go on a diet.
2) to express expectations:
- Are you ready? The taxi should be here soon.
- Twenty dollars is enough. It shouldn’t cost more than that.
3) to suggest a less strong possibility
- If you should pass the bakery, can you buy some bread?
4) Should with present perfect tense means something in the past should not be done.
- The baby is crying. You shouldn’t have talked so loudly.
- Mom is angry. You shouldn’t have come back so late.
Must &Have to: must/have to are used to
1) express something is necessary and essential
- You must pay by cash.
- You have to drive on the right in France.
2) Students have to wear uniform.
- must not is used to express something is not permitted or allowed.
- You mustn’t smoke, eat and drink in the museum.
- You must not drink and drive.
3) not have to is used to express something that is not to be done necessarily.
- We don’t have to get up early on Saturday.
- She doesn’t have to live in the hotel. She can live with us.
May: May is used to
1) express possibility in the present or in the future.
- It may rain.
- Elizabeth may know his telephone number.
2) for permission:
- May I come in?
- You may come if you want.
3) to express wish or hope.
- May you a long life!
Might: Might is used
1) to express possibility in the present or in the future.
- Ashley might be in the library. I am not sure.
- George might come as well.
- He might come. (the chance that he comes is less likely than may)
2) might with present perfect tense means speculation about the past.
- Edward is late. He might have missed his bus or he might have overslept.